For the sake of concreteness, in this section we use the example of a bipartite network in which authors (agents) are linked to the papers they have written (artifacts). The projection of such a network yields a co-authorship network in which the edge weight between a pair of authors indicates their number of co-authored papers.[1]} These edge weight values will depend heavily on the distribution of papers written by authors (i.e., the agent degree sequence), and on the distribution of authors on each paper (i.e., the artifact degree sequence). Different distributions describe different kinds of scholarly environments as shown in Table REF . The choice of a backbone model affects how and whether these distributions are considered, and in this example affects the extent to which decisions about the significance of two authors' number of co-authored papers consider the scholarly environment. The FDSM compares their observed number of co-authored papers to the number that might be observed in alternative realizations of the same environment, while other backbone models relax the extent to which the environment is held constant.
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